The background description provided herein is for the purpose of generally presenting the context of the disclosure. Work of the presently named inventors, to the extent it is described in this background section, as well as aspects of the description that may not otherwise qualify as prior art at the time of filing, are neither expressly nor impliedly admitted as prior art against the present disclosure.
With the mass demand for the high transmission rate of electronic products, most electrical connectors nowadays have to consider high frequency requirements. A conventional electrical connector is used for implementing an electrical connection between an electronic card and a circuit board to achieve signal transmission. The electrical connector has an insulating shell, the front end thereof has an insertion slot for accommodating an electronic card, and the rear end thereof has a mounting slot for accommodating a terminal module. The terminal module has multiple terminals and an insulating block injection-molded with the terminals. The terminals include multiple pairs of differential signal terminals for transmitting high-frequency signals and multiple ground terminals respectively located between each two adjacent pairs of differential signal terminals. Each of the terminals has a fixing portion embedded in the insulating block. A contact arm extends from the front end of the fixing portion and extends forward out of the insulating block, and is exposed in the insertion slot for electrically contacting the electronic card. A soldering portion extends backward from the rear end of the fixing portion out of the insulating block for electrically connecting a circuit board.
However, the fixing portion is embedded in the insulating block, and the elastic arm is exposed to the air. When the signal is transmitted from the fixing portion to the elastic arm, the dielectric constant of the air is less than the dielectric constant of the insulating block, and the capacitance between the ground terminal and the adjacent differential signal terminal decreases due to the decrease of the dielectric constant, thereby resulting in a change in the impedance between the ground terminal and the adjacent differential signal terminal, and causing high-speed signal loss and crosstalk.
Therefore, a heretofore unaddressed need to design a new electrical connector exists in the art to address the aforementioned deficiencies and inadequacies.